The Defense Department will notify Congress as early as Wednesday of plans to furlough almost 800,000 civilian employees starting in April if automatic budget cuts take effect, according to a defense official.

That timetable is still subject to change, the official, speaking on condition of anonymity, said Tuesday afternoon.

By law, however, DoD must give lawmakers 45 days notice of employee furloughs. If the spending cuts, formally known as sequestration, begin as scheduled March 1, the Pentagon will likely send most civilians home for one day per week for up to 22 weeks through the end of the fiscal year in September, Deputy Defense Secretary Ashton Carter told a House committee last week.

The furloughs would save DoD about $5 billion out of the $46 billion total it will have to cut under sequestration, Carter said. Military personnel would be exempt.

The department would have to give employees at least 30 days notice of any furloughs.

Under Office of Personnel Management policy, agencies in general have some discretion in deciding whom to send home, depending on the importance of individual jobs to the agency’s mission and other factors.

But the Navy would make only “minimal exceptions,” according to guidance released at a labor-management meeting last week and posted on an American Federation of Government Employees website. Among them would be workers needed to protect life and property, employees deployed to a combat zone and presidential appointees confirmed by the Senate. If furloughs are needed for its civilian workforce of almost 200,000, the Navy would begin them the week of April 21, the guidance indicates.